An Essay
Concerning
Human
Understanding
by John Locke
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Human Understanding
foundations: or at least, if mine prove a castle in the air,
I will endeavour it shall be all of a piece and hang together.
Wherein I warn the reader not to expect undeniable
cogent demonstrations, unless I may be allowed the
privilege, not seldom assumed by others, to take my
principles for granted; and then, I doubt not, but I can
demonstrate too. All that I shall say for the principles I
proceed on is, that I can only appeal to men’s own unprejudiced
experience and observation whether they be
true or not; and this is enough for a man who professes
no more than to lay down candidly and freely his own
conjectures, concerning a subject lying somewhat in the
dark, without any other design than an unbiased inquiry
after truth.
BOOK II
Of Ideas
Chapter I
Of Ideas in general, and their Original
1. Idea is the object of thinking. Every man being conscious
to himself that he thinks; and that which his
mind is applied about whilst thinking being the ideas
that are there, it is past doubt that men have in their
minds several ideas,—such as are those expressed by
the words whiteness, hardness, sweetness, thinking,
motion, man, elephant, army, drunkenness, and others:
it is in the first place then to be inquired, How he comes
by them?
I know it is a received doctrine, that men have native
ideas, and original characters, stamped upon their minds
in their very first being. This opinion I have at large
examined already; and, I suppose what I have said in
the foregoing Book will be much more easily admitted,
when I have shown whence the understanding may get
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all the ideas it has; and by what ways and degrees they
may come into the mind;—for which I shall appeal to
every one’s own observation and experience.
2. All ideas come from sensation or reflection. Let us
then suppose the mind to be, as we say, white paper,
void of all characters, without any ideas:—How comes
it to be furnished? Whence comes it by that vast store
which the busy and boundless fancy of man has painted
on it with an almost endless variety? Whence has it all
the materials of reason and knowledge? To this I answer,
in one word, from experience. In that all our knowledge
is founded; and from that it ultimately derives itself.
Our observation employed either, about external sensible
objects, or about the in ternal operations of our
minds perceived and reflected on by ourselves, is that
which supplies our understandings with all the materials
of thinking. These two are the fountains of knowledge,
from whence all the ideas we have, or can naturally
have, do spring.
3. The objects of sensation one source of ideas. First,
our Senses, conversant about particular sensible objects,
do convey into the mind several distinct perceptions of
things, according to those various ways wherein those
objects do affect them. And thus we come by those ideas
we have of yellow, white, heat, cold, soft, hard, bitter,
sweet, and all those which we call sensible qualities;
which when I say the senses convey into the mind, I
mean, they from external objects convey into the mind
what produces there those perceptions. This great source
of most of the ideas we have, depending wholly upon
our senses, and derived by them to the understanding,
I call sensation.
4. The operations of our minds, the other source of
them. Secondly, the other fountain from which experience
furnisheth the understanding with ideas is,—the
perception of the operations of our own mind within
us, as it is employed about the ideas it has got;—which
operations, when the soul comes to reflect on and consider,
do furnish the understanding with another set of
ideas, which could not be had from things without. And
such are perception, thinking, doubting, believing, reasoning,
knowing, willing, and all the different actings
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of our own minds;—which we being conscious of, and
observing in ourselves, do from these receive into our
understandings as distinct ideas as we do from bodies
affecting our senses. This source of ideas every man has
wholly in himself; and though it be not sense, as having
nothing to do with external objects, yet it is very like
it, and might properly enough be called internal sense.
But as I call the other sensation, so I Call this reflection,
the ideas it affords being such only as the mind gets by
reflecting on its own operations within itself. By reflection
then, in the following part of this discourse, I would
be understood to mean, that notice which the mind
takes of its own operations, and the manner of them, by
reason whereof there come to be ideas of these operations
in the understanding. These two, I say, viz. external
material things, as the objects of sensation, and the
operations of our own minds within, as the objects of
reflection, are to me the only originals from whence all
our ideas take their beginnings. The term operations
here I use in a large sense, as comprehending not barely
the actions of the mind about its ideas, but some sort of
passions arising sometimes from them, such as is the
satisfaction or uneasiness arising from any thought.
5. All our ideas are of the one or the other of these.
The understanding seems to me not to have the least
glimmering of any ideas which it doth not receive from
one of these two. External objects furnish the mind
with the ideas of sensible qualities, which are all those
different perceptions they produce in us; and the mind
furnishes the understanding with ideas of its own operations.
These, when we have taken a full survey of
them, and their several modes, combinations, and relations,
we shall find to contain all our whole stock of
ideas; and that we have nothing in our minds which did
not come in one of these two ways. Let any one examine
his own thoughts, and thoroughly search into his
understanding; and then let him tell me, whether all
the original ideas he has there, are any other than of
the objects of his senses, or of the operations of his
mind, considered as objects of his reflection. And how
great a mass of knowledge soever he imagines to be lodged
there, he will, upon taking a strict view, see that he has
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not any idea in his mind but what one of these two
have imprinted;—though perhaps, with infinite variety
compounded and enlarged by the understanding, as we
shall see hereafter.
6. Observable in children. He that attentively considers
the state of a child, at his first coming into the world,
will have little reason to think him stored with plenty of
ideas, that are to be the matter of his future knowledge.
It is by degrees he comes to be furnished with them.
And though the ideas of obvious and familiar qualities
imprint themselves before the memory begins to keep a
register of time or order, yet it is often so late before
some unusual qualities come in the way, that there are
few men that cannot recollect the beginning of their
acquaintance with them. And if it were worth while, no
doubt a child might be so ordered as to have but a very
few, even of the ordinary ideas, till he were grown up to
a man. But all that are born into the world, being surrounded
with bodies that perpetually and diversely affect
them, variety of ideas, whether care be taken of it
or not, are imprinted on the minds of children. Light
and colours are busy at hand everywhere, when the eye
is but open; sounds and some tangible qualities fail not
to solicit their proper senses, and force an entrance to
the mind;—but yet, I think, it will be granted easily,
that if a child were kept in a place where he never saw
any other but black and white till he were a man, he
would have no more ideas of scarlet or green, than he
that from his childhood never tasted an oyster, or a
pine-apple, has of those particular relishes.
7. Men are differently furnished with these, according
to the different objects they converse with. Men then
come to be furnished with fewer or more simple ideas
from without, according as the objects they converse
with afford greater or less variety; and from the operations
of their minds within, according as they more or
less reflect on them. For, though he that contemplates
the operations of his mind, cannot but have plain and
clear ideas of them; yet, unless he turn his thoughts
that way, and considers them attentively, he will no
more have clear and distinct ideas of all the operations
of his mind, and all that may be observed therein, than
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he will have all the particular ideas of any landscape, or
of the parts and motions of a clock, who will not turn
his eyes to it, and with attention heed all the parts of it.
The picture, or clock may be so placed, that they may
come in his way every day; but yet he will have but a
confused idea of all the parts they are made up of, till he
applies himself with attention, to consider them each in
particular.
8. Ideas of reflection later, because they need attention.
And hence we see the reason why it is pretty late
before most children get ideas of the operations of their
own minds; and some have not any very clear or perfect
ideas of the greatest part of them all their lives. Because,
though they pass there continually, yet, like floating
visions, they make not deep impressions enough to
leave in their mind clear, distinct, lasting ideas, till the
understanding turns inward upon itself, reflects on its
own operations, and makes them the objects of its own
contemplation. Children when they come first into it,
are surrounded with a world of new things, which, by a
constant solicitation of their senses, draw the mind constantly
to them; forward to take notice of new, and apt
to be delighted with the variety of changing objects.
Thus the first years are usually employed and diverted
in looking abroad. Men’s business in them is to acquaint
themselves with what is to be found without; and so
growing up in a constant attention to outward sensations,
seldom make any considerable reflection on what
passes within them, till they come to be of riper years;
and some scarce ever at all.
9. The soul begins to have ideas when it begins to perceive.
To ask, at what time a man has first any ideas, is
to ask, when he begins to perceive;—having ideas, and
perception, being the same thing. I know it is an opinion,
that the soul always thinks, and that it has the
actual perception of ideas in itself constantly, as long as
it exists; and that actual thinking is as inseparable from
the soul as actual extension is from the body; which if
true, to inquire after the beginning of a man’s ideas is
the same as to inquire after the beginning of his soul.
For, by this account, soul and its ideas, as body and its
extension, will begin to exist both at the same time.
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10. The soul thinks not always; for this wants proofs.
But whether the soul be supposed to exist antecedent
to, or coeval with, or some time after the first rudiments
of organization, or the beginnings of life in the
body, I leave to be disputed by those who have better
thought of that matter. I confess myself to have one of
those dull souls, that doth not perceive itself always to
contemplate ideas; nor can conceive it any more necessary
for the soul always to think, than for the body
always to move: the perception of ideas being (as I conceive)
to the soul, what motion is to the body; not its
essence, but one of its operations. And therefore, though
thinking be supposed never so much the proper action
of the soul, yet it is not necessary to suppose that it
should be always thinking, always in action. That, perhaps,
is the privilege of the infinite Author and Preserver
of all things, who “never slumbers nor sleeps;”
but is not competent to any finite being, at least not to
the soul of man. We know certainly, by experience, that
we sometimes think; and thence draw this infallible consequence,—that
there is something in us that has a
power to think. But whether that substance perpetually
thinks or no, we can be no further assured than
experience informs us. For, to say that actual thinking
is essential to the soul, and inseparable from it, is to beg
what is in question, and not to prove it by reason;—
which is necessary to be done, if it be not a self-evident
proposition. But whether this, “That the soul always
thinks,” be a self-evident proposition, that everybody
assents to at first hearing, I appeal to mankind. It is
doubted whether I thought at all last night or no. The
question being about a matter of fact, it is begging it to
bring, as a proof for it, an hypothesis, which is the very
thing in dispute: by which way one may prove anything,
and it is but supposing that all watches, whilst
the balance beats, think, and it is sufficiently proved,
and past doubt, that my watch thought all last night.
But he that would not deceive himself, ought to build
his hypothesis on matter of fact, and make it out by
sensible experience, and not presume on matter of fact,
because of his hypothesis, that is, because he supposes
it to be so; which way of proving amounts to this, that
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I must necessarily think all last night, because another
supposes I always think, though I myself cannot perceive
that I always do so.
But men in love with their opinions may not only
suppose what is in question, but allege wrong matter of
fact. How else could any one make it an inference of
mine, that a thing is not, because we are not sensible of
it in our sleep? I do not say there is no soul in a man,
because he is not sensible of it in his sleep; but I do say,
he cannot think at any time, waking or sleeping: without
being sensible of it. Our being sensible of it is not
necessary to anything but to our thoughts; and to them
it is; and to them it always will be necessary, till we can
think without being conscious of it.
11. It is not always conscious of it. I grant that the
soul, in a waking man, is never without thought, because
it is the condition of being awake. But whether
sleeping without dreaming be not an affection of the
whole man, mind as well as body, may be worth a waking
man’s consideration; it being hard to conceive that
anything should think and not be conscious of it. If the
soul doth think in a sleeping man without being conscious
of it, I ask whether, during such thinking, it has
any pleasure or pain, or be capable of happiness or misery?
I am sure the man is not; no more than the bed or
earth he lies on. For to be happy or miserable without
being conscious of it, seems to me utterly inconsistent
and impossible. Or if it be possible that the soul can,
whilst the body is sleeping, have its thinking, enjoyments,
and concerns, its pleasures or pain, apart, which
the man is not conscious of nor partakes in,—it is certain
that Socrates asleep and Socrates awake is not the
same person; but his soul when he sleeps, and Socrates
the man, consisting of body and soul, when he is waking,
are two persons: since waking Socrates has no knowledge
of, or concernment for that happiness or misery of
his soul, which it enjoys alone by itself whilst he sleeps,
without perceiving anything of it; no more than he has
for the happiness or misery of a man in the Indies, whom
he knows not. For, if we take wholly away all consciousness
of our actions and sensations, especially of pleasure
and pain, and the concernment that accompanies it, it
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will be hard to know wherein to place personal identity.
12. If a sleeping man thinks without knowing it, the
sleeping and waking man are two persons. The soul,
during sound sleep, thinks, say these men. Whilst it
thinks and perceives, it is capable certainly of those of
delight or trouble, as well as any other perceptions; and
it must necessarily be conscious of its own perceptions.
But it has all this apart: the sleeping man, it is plain, is
conscious of nothing of all this. Let us suppose, then,
the soul of Castor, while he is sleeping, retired from his
body; which is no impossible supposition for the men I
have here to do with, who so liberally allow life, without
a thinking soul, to all other animals. These men
cannot then judge it impossible, or a contradiction, that
the body should live without the soul; nor that the soul
should subsist and think, or have perception, even perception
of happiness or misery, without the body. Let
us then, I say, suppose the soul of Castor separated
during his sleep from his body, to think apart. Let us
suppose, too, that it chooses for its scene of thinking
the body of another man, v.g. Pollux, who is sleeping
without a soul. For, if Castor’s soul can think, whilst
Castor is asleep, what Castor is never conscious of, it is
no matter what place it chooses to think in. We have
here, then, the bodies of two men with only one soul
between them, which we will suppose to sleep and wake
by turns; and the soul still thinking in the waking man,
whereof the sleeping man is never conscious, has never
the least perception. I ask, then, whether Castor and
Pollux, thus with only one soul between them, which
thinks and perceives in one what the other is never
conscious of, nor is concerned for, are not two as distinct
persons as Castor and Hercules, or as Socrates and
Plato were? And whether one of them might not be
very happy, and the other very miserable? Just by the
same reason, they make the soul and the man two persons,
who make the soul think apart what the man is
not conscious of. For, I suppose nobody will make identity
of persons to consist in the soul’s being united to
the very same numercial particles of matter. For if that
be necessary to identity, it will be impossible, in that
constant flux of the particles of our bodies, that any
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man should be the same person two days, or two moments,
together.
13. Impossible to convince those that sleep without
dreaming, that they think. Thus, methinks, every drowsy
nod shakes their doctrine, who teach that the soul is
always thinking. Those, at least, who do at any time
sleep without dreaming, can never be convinced that
their thoughts are sometimes for four hours busy without
their knowing of it; and if they are taken in the
very act, waked in the middle of that sleeping contemplation,
can give no manner of account of it.
14. That men dream without remembering it, in vain
urged. It will perhaps be said,—That the soul thinks
even in the soundest sleep, but the memory retains it
not. That the soul in a sleeping man should be this
moment busy a thinking, and the next moment in a
waking man not remember nor be able to recollect one
jot of all those thoughts, is very hard to be conceived,
and would need some better proof than bare assertion
to make it be believed. For who can without any more
ado, but being barely told so, imagine that the greatest
part of men do, during all their lives, for several hours
every day, think of something, which if they were asked,
even in the middle of these thoughts, they could remember
nothing at all of? Most men, I think, pass a
great part of their sleep without dreaming. I once knew
a man that was bred a scholar, and had no bad memory,
who told me he had never dreamed in his life, till he had
that fever he was then newly recovered of, which was
about the five or six and twentieth year of his age. I
suppose the world affords more such instances: at least
every one’s acquaintance will furnish him with examples
enough of such as pass most of their nights without
dreaming.
15. Upon this hypothesis, the thoughts of a sleeping
man ought to be most rational. To think often, and
never to retain it so much as one moment, is a very
useless sort of thinking; and the soul, in such a state of
thinking, does very little, if at all, excel that of a looking-glass,
which constantly receives variety of images,
or ideas, but retains none; they disappear and vanish,
and there remain no footsteps of them; the looking-
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glass is never the better for such ideas, nor the soul for
such thoughts. Perhaps it will be said, that in a waking
man the materials of the body are employed, and made
use of, in thinking; and that the memory of thoughts is
retained by the impressions that are made on the brain,
and the traces there left after such thinking; but that in
the thinking of the soul, which is not perceived in a
sleeping man, there the soul thinks apart, and making no
use of the organs of the body, leaves no impressions on
it, and consequently no memory of such thoughts. Not
to mention again the absurdity of two distinct persons,
which follows from this supposition, I answer, further,—
That whatever ideas the mind can receive and contemplate
without the help of the body, it is reasonable to
conclude it can retain without the help of the body too;
or else the soul, or any separate spirit, will have but little
advantage by thinking. If it has no memory of its own
thoughts; if it cannot lay them up for its own use, and be
able to recall them upon occasion; if it cannot reflect
upon what is past, and make use of its former experiences,
reasonings, and contemplations, to what purpose
does it think? They who make the soul a thinking thing,
at this rate, will not make it a much more noble being
than those do whom they condemn, for allowing it to be
nothing but the subtilist parts of matter. Characters drawn
on dust, that the first breath of wind effaces; or impressions
made on a heap of atoms, or animal spirits, are
altogether as useful, and render the subject as noble, as
the thoughts of a soul that perish in thinking; that, once
out of sight, are gone forever, and leave no memory of
themselves behind them. Nature never makes excellent
things for mean or no uses: and it is hardly to be conceived
that our infinitely wise Creator should make so
admirable a faculty which comes nearest the excellency of
his own incomprehensible being, to be so idly and uselessly
employed, at least a fourth part of its time here, as
to think constantly, without remembering any of those
thoughts, without doing any good to itself or others, or
being any way useful to any other part of the creation, If
we will examine it, we shall not find, I suppose, the motion
of dull and senseless matter, any where in the universe,
made so little use of and so wholly thrown away.
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16. On this hypothesis, the soul must have ideas not
derived from sensation or reflection, of which there is
no appearance. It is true, we have sometimes instances
of perception whilst we are asleep, and retain the memory
of those thoughts: but how extravagant and incoherent
for the most part they are; how little conformable to
the perfection and order of a rational being, those who
are acquainted with dreams need not be told. This I
would willingly be satisfied in,—whether the soul, when
it thinks thus apart, and as it were separate from the
body, acts less rationally than when conjointly with it,
or no. If its separate thoughts be less rational, then
these men must say, that the soul owes the perfection
of rational thinking to the body: if it does not, it is a
wonder that our dreams should be, for the most part, so
frivolous and irrational; and that the soul should retain
none of its more rational soliloquies and meditations.
17. If I think when I know it not, nobody else can
know it. Those who so confidently tell us that the soul
always actually thinks, I would they would also tell us,
what those ideas are that are in the soul of a child,
before or just at the union with the body, before it hath
received any by sensation. The dreams of sleeping men
are, as I take it, all made up of the waking man’s ideas;
though for the most part oddly put together. It is strange,
if the soul has ideas of its own that it derived not from
sensation or reflection, (as it must have, if it thought
before it received any impressions from the body,) that
it should never, in its private thinking, (so private, that
the man himself perceives it not,) retain any of them
the very moment it wakes out of them, and then make
the man glad with new discoveries. Who can find it reason
that the soul should, in its retirement during sleep,
have so many hours’ thoughts, and yet never light on
any of those ideas it borrowed not from sensation or
reflection; or at least preserve the memory of none but
such, which, being occasioned from the body, must needs
be less natural to a spirit? It is strange the soul should
never once in a man’s whole life recall over any of its
pure native thoughts, and those ideas it had before it
borrowed anything from the body; never bring into the
waking man’s view any other ideas but what have a
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tang of the cask, and manifestly derive their original
from that union. If it always thinks, and so had ideas
before it was united, or before it received any from the
body, it is not to be supposed but that during sleep it
recollects its native ideas; and during that retirement
from communicating with the body, whilst it thinks by
itself, the ideas it is busied about should be, sometimes
at least, those more natural and congenial ones which it
had in itself, underived from the body, or its own operations
about them: which, since the waking man never
remembers, we must from this hypothesis conclude either
that the soul remembers something that the man
does not; or else that memory belongs only to such
ideas as are derived from the body, or the mind’s operations
about them.
18. How knows any one that the soul always thinks?
For if it be not a self-evident proposition, it needs proof.
I would be glad also to learn from these men who so
confidently pronounce that the human soul, or, which
is all one, that a man always thinks, how they come to
know it; nay, how they come to know that they themselves
think when they themselves do not perceive it.
This, I am afraid, is to be sure without proofs, and to
know without perceiving. It is, I suspect, a confused
notion, taken up to serve an hypothesis; and none of
those clear truths, that either their own evidence forces
us to admit, or common experience makes it impudence
to deny. For the most that can be said of it is, that it is
possible the soul may always think, but not always retain
it in memory. And I say, it is as possible that the
soul may not always think; and much more probable
that it should sometimes not think, than that it should
often think, and that a long while together, and not be
conscious to itself, the next moment after, that it had
thought.
19. “That a man should be busy in thinking, and yet
not retain it the next moment,” very improbable. To
suppose the soul to think, and the man not to perceive
it, is, as has been said, to make two persons in one man.
And if one considers well these men’s way of speaking,
one should be led into a suspicion that they do so. For
they who tell us that the soul always thinks, do never,
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that I remember, say that a man always thinks. Can the
soul think, and not the man? Or a man think, and not
be conscious of it? This, perhaps, would be suspected of
jargon in others. If they say the man thinks always, but
is not always conscious of it, they may as well say his
body is extended without having parts. For it is altogether
as intelligible to say that a body is extended without
parts, as that anything thinks without being conscious
of it, or perceiving that it does so. They who talk
thus may, with as much reason, if it be necessary to
their hypothesis, say that a man is always hungry, but
that he does not always feel it; whereas hunger consists
in that very sensation, as thinking consists in being
conscious that one thinks. If they say that a man is
always conscious to himself of thinking, I ask, How they
know it? Consciousness is the perception of what passes
in a man’s own mind. Can another man perceive that I
am conscious of anything, when I perceive it not myself?
No man’s knowledge here can go beyond his experience.
Wake a man out of a sound sleep, and ask him
what he was that moment thinking of. If he himself be
conscious of nothing he then thought on, he must be a
notable diviner of thoughts that can assure him that he
was thinking. May he not, with more reason, assure
him he was not asleep? This is something beyond philosophy;
and it cannot be less than revelation, that discovers
to another thoughts in my mind, when I can find
none there myself, And they must needs have a penetrating
sight who can certainly see that I think, when
I cannot perceive it myself, and when I declare that I do
not; and yet can see that dogs or elephants do not think,
when they give all the demonstration of it imaginable,
except only telling us that they do so. This some may
suspect to be a step beyond the Rosicrucians; it seeming
easier to make one’s self invisible to others, than to
make another’s thoughts visible to me, which are not
visible to himself. But it is but defining the soul to be “a
substance that always thinks,” and the business is done.
If such definition be of any authority, I know not what
it can serve for but to make many men suspect that
they have no souls at all; since they find a good part of
their lives pass away without thinking. For no defini-
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tions that I know, no suppositions of any sect, are of
force enough to destroy constant experience; and perhaps
it is the affectation of knowing beyond what we
perceive, that makes so much useless dispute and noise
in the world.
20. No ideas but from sensation and reflection, evident,
if we observe children. I see no reason, therefore,
to believe that the soul thinks before the senses have
furnished it with ideas to think on; and as those are
increased and retained, so it comes, by exercise, to improve
its faculty of thinking in the several parts of it; as
well as, afterwards, by compounding those ideas, and
reflecting on its own operations, it increases its stock,
as well as facility in remembering, imagining, reasoning,
and other modes of thinking.
21. State of a child in the mother’s womb. He that will
suffer himself to be informed by observation and experience,
and not make his own hypothesis the rule of nature,
will find few signs of a soul accustomed to much
thinking in a new-born child, and much fewer of any
reasoning at all. And yet it is hard to imagine that the
rational soul should think so much, and not reason at
all. And he that will consider that infants newly come
into the world spend the greatest part of their time in
sleep, and are seldom awake but when either hunger
calls for the teat, or some pain (the most importunate
of all sensations), or some other violent impression on
the body, forces the mind to perceive and attend to
it;—he, I say, who considers this, will perhaps find reason
to imagine that a foetus in the mother’s womb differs
not much from the state of a vegetable, but passes
the greatest part of its time without perception or
thought; doing very little but sleep in a place where it
needs not seek for food, and is surrounded with liquor,
always equally soft, and near of the same temper; where
the eyes have no light, and the ears so shut up are not
very susceptible of sounds; and where there is little or
no variety, or change of objects, to move the senses.
22. The mind thinks in proportion to the matter it gets
from experience to think about. Follow a child from its
birth, and observe the alterations that time makes, and
you shall find, as the mind by the senses comes more
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and more to be furnished with ideas, it comes to be
more and more awake; thinks more, the more it has
matter to think on. After some time it begins to know
the objects which, being most familiar with it, have
made lasting impressions. Thus it comes by degrees to
know the persons it daily converses with, and distinguishes
them from strangers; which are instances and
effects of its coming to retain and distinguish the ideas
the senses convey to it. And so we may observe how the
mind, by degrees, improves in these; and advances to
the exercise of those other faculties of enlarging, compounding,
and abstracting its ideas, and of reasoning
about them, and reflecting upon all these; of which I
shall have occasion to speak more hereafter.
23. A man begins to have ideas when he first has sensation.
What sensation is. If it shall be demanded then,
when a man begins to have any ideas, I think the true
answer is,—when he first has any sensation. For, since
there appear not to be any ideas in the mind before the
senses have conveyed any in, I conceive that ideas in
the understanding are coeval with sensation; which is
such an impression or motion made in some part of the
body, as produces some perception in the understanding.
It is about these impressions made on our senses by
outward objects that the mind seems first to employ
itself, in such operations as we call perception, remembering,
consideration, reasoning, &c.
24. The original of all our knowledge. In time the mind
comes to reflect on its own operations about the ideas
got by sensation, and thereby stores itself with a new
set of ideas, which I call ideas of reflection. These are
the impressions that are made on our senses by outward
objects that are extrinsical to the mind; and its own
operations, proceeding from powers intrinsical and proper
to itself, which, when reflected on by itself, become
also objects of its contemplation—are, as I have said,
the original of all knowledge. Thus the first capacity of
human intellect is,—that the mind is fitted to receive
the impressions made on it; either through the senses
by outward objects, or by its own operations when it
reflects on them. This is the first step a man makes
towards the discovery of anything, and the groundwork
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whereon to build all those notions which ever he shall
have naturally in this world. All those sublime thoughts
which tower above the clouds, and reach as high as
heaven itself, take their rise and footing here: in all that
great extent wherein the mind wanders, in those remote
speculations it may seem to be elevated with, it
stirs not one jot beyond those ideas which sense or reflection
have offered for its contemplation.
25. In the reception of simple ideas, the understanding
is for the most part passive. In this part the understanding
is merely passive; and whether or no it will
have these beginnings, and as it were materials of knowledge,
is not in its own power. For the objects of our
senses do, many of them, obtrude their particular ideas
upon our minds whether we will or not; and the operations
of our minds will not let us be without, at least,
some obscure notions of them. No man can be wholly
ignorant of what he does when he thinks. These simple
ideas, when offered to the mind, the understanding can
no more refuse to have, nor alter when they are imprinted,
nor blot them out and make new ones itself,
than a mirror can refuse, alter, or obliterate the images
or ideas which the objects set before it do therein produce.
As the bodies that surround us do diversely affect
our organs, the mind is forced to receive the impressions;
and cannot avoid the perception of those ideas
that are annexed to them.
Chapter II
Of Simple Ideas
1. Uncompounded appearances. The better to understand
the nature, manner, and extent of our knowledge,
one thing is carefully to be observed concerning the
ideas we have; and that is, that some of them are simple
and some complex.
Though the qualities that affect our senses are, in the
things themselves, so united and blended, that there is
no separation, no distance between them; yet it is plain,
the ideas they produce in the mind enter by the senses
simple and unmixed. For, though the sight and touch
often take in from the same object, at the same time,